| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rotation detector which is an absolute encoder using a magnetic sensor, a bias magnet and a magnetic body gear having high resolution, high durability and high reliability. <P>SOLUTION: A rotation detector comprises: two magnetic body gears 1, 2 attached coaxially to a rotation axis 5 of a rotation body; two magnetic sensors 7, 8 arranged to face the magnetic body gears 1, 2, respectively; and a bias magnet 6 arranged so that magnetic flux density applied to the magnetic sensors 7, 8 changes according to rotation of the magnetic body gears 1, 2. Each of the magnetic sensor 7, 8 is an absolute encoder that outputs only one phase of A/B phase sine wave output having 90-degree phase difference per tooth, according to the rotation of the magnetic body gears 1, 2, and is configured so that numbers of teeth of the magnetic body gears 1, 2 are different by only one tooth. <P>COPYRIGHT: (C)2012,JPO&INPIT |
